Decay of eddies at the South-West Indian Ridge

South African Journal of Science

 
 
Field Value
 
Title Decay of eddies at the South-West Indian Ridge
 
Creator Durgadoo, Jonathan V. Ansorge, Isabelle J. de Cuevas, Beverly A. Lutjeharms, Johann R.E. Coward, Andrew C.
 
Subject Physical Oceanography eddy kinetic energy hotspot; Southern Ocean; DEIMEC; OCCAM; Prince Edward Islands
Description The South-West Indian Ridge in the Indian sector of the Southern Ocean is a region recognised for the creation of particularly intense eddy disturbances in the mean flow of the Antarctic Circumpolar Current. Eddies formed at this ridge have been extensively studied over the past decade using hydrographic, satellite, drifter and float data and it is hypothesised that they could provide a vehicle for localised meridional heat and salt exchange. The effectiveness of this process is dependent on the rate of decay of the eddies. However, in order to investigate eddy decay, logistically difficult hydrographic monitoring is required. This study presents the decay of cold eddies at the South-West Indian Ridge, using outputs from a high-resolution ocean model. The model’s representation of the dynamic nature of this region is fully characteristic of observations. On average, 3–4 intense and well-defined cold eddies are generated per year; these eddies have mean longevities of 5.0±2.2 months with average advection speeds of 5±2 km/day. Most simulated eddies reach their peak intensity within 1.5–2.5 months after genesis and have depths of 2000 m – 3000 m. Thereafter they dissipate within approximately 3 months. The decay of eddies is generally characterised by a decrease in their sea surface height signature, a weakening in their rotation rates and a modification in their temperature–salinity characteristics. Subantarctic top predators are suspected to forage preferentially along the edges of eddies. The process of eddy dissipation may thus influence their feeding behaviour.
 
Publisher AOSIS
 
Contributor University of Cape town and South African National Antarctic Programme
Date 2011-11-03
 
Type info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion — hydrographic and model data analysis
Format application/pdf text/html application/epub+zip text/xml
Identifier 10.4102/sajs.v107i11/12.673
 
Source South African Journal of Science; Vol 107, No 11/12 (2011); 10 pages 1996-7489 0038-2353
 
Language eng
 
Relation
The following web links (URLs) may trigger a file download or direct you to an alternative webpage to gain access to a publication file format of the published article:

https://journals.sajs.aosis.co.za/index.php/sajs/article/view/673/849 https://journals.sajs.aosis.co.za/index.php/sajs/article/view/673/933 https://journals.sajs.aosis.co.za/index.php/sajs/article/view/673/940 https://journals.sajs.aosis.co.za/index.php/sajs/article/view/673/935 https://journals.sajs.aosis.co.za/index.php/sajs/article/downloadSuppFile/673/2906 https://journals.sajs.aosis.co.za/index.php/sajs/article/downloadSuppFile/673/2907 https://journals.sajs.aosis.co.za/index.php/sajs/article/downloadSuppFile/673/2908 https://journals.sajs.aosis.co.za/index.php/sajs/article/downloadSuppFile/673/2909 https://journals.sajs.aosis.co.za/index.php/sajs/article/downloadSuppFile/673/2910 https://journals.sajs.aosis.co.za/index.php/sajs/article/downloadSuppFile/673/2911 https://journals.sajs.aosis.co.za/index.php/sajs/article/downloadSuppFile/673/2912 https://journals.sajs.aosis.co.za/index.php/sajs/article/downloadSuppFile/673/2913 https://journals.sajs.aosis.co.za/index.php/sajs/article/downloadSuppFile/673/2914 https://journals.sajs.aosis.co.za/index.php/sajs/article/downloadSuppFile/673/2915
 
Coverage Southern Ocean n/a n/a
Rights Copyright (c) 2011 Jonathan V. Durgadoo, Isabelle J. Ansorge, Beverly A. de Cuevas, Johann R.E. Lutjeharms, Andrew C. Coward https://creativecommons.org/licenses/by/4.0
ADVERTISEMENT